Energy‐Saving Hydrogen Production by Seawater Electrolysis Coupling Sulfion Degradation

Abstract

Electrolysis of costless and infinite seawater is a promising way toward grid‐scale hydrogen production without causing freshwater stress. Practical potential of this technology, however, is hindered by low energy efficiency and anode corrosion by the detrimental chlorine chemistry in seawater in addition to unaffordable electricity expense. Herein, energy‐saving hydrogen production is reported by chlorine‐free seawater splitting coupling sulfion oxidation. It yields hydrogen at a low cell voltage of 0.97 V, cutting the electricity consumption to 2.32 kWh per m3 H2 at 300 mA cm−2. Compared to alkaline water electrolysis, the energy expense is primarily saved by 60% with 50% lower energy equivalent input. Benefiting from the ultralow cell voltage, the hazardous chlorine chemistry is fully avoided without anode corrosion regardless of Cl− crossover. Meanwhile, it also allows fast degradation of S2− pollutant from the water body to value‐added sulfur with 80% efficiency, for further reducing hydrogen cost and protection of the ecosystem. Connecting such a hybrid seawater electrolyzer to a commercial solar cell can harvest the hydrogen from seawater with better sustainability. This work may offer new opportunities for low‐cost hydrogen production from the unlimited ocean resources with environmental protection.

Amorphous-crystalline PdRu bimetallene for efficient hydrogen evolution electrocatalysis

“…1–3 Electrochemical water splitting is considered as one of the economic and convenient strategies to produce hydrogen. 4–6 However, this method suffers from high operation voltage due to slow reaction kinetics, so it is necessary to enhance the reaction rate and improve the catalytic activity for the hydrogen evolution reaction (HER). Currently, noble metal-based catalysts are considered to be one of the best HER catalysts.…”

Hydrogen Production Technology Promotes the Analysis and Prospect of the Hydrogen Fuel Cell Vehicles Development under the Background of Carbon Peak and Carbon Neutrality in China

“…Therefore, large-scale hydrogen production from fresh water is basically impossible, which makes the idea of adjusting the energy structure and improving the global environment through green hydrogen empty talk. Moreover, seawater is the most abundant resource in the world (96.5% of the world’s water is seawater); − if seawater desalination can be carried out to produce hydrogen, and cooperate with the advanced wind power, it not only can improve the utilization rate of long-distance wind power generation but also can generate green hydrogen energy and obtain high-purity fresh water. , As a result, such a combination can achieve the dual purpose of seawater purification and hydrogen production and alleviate the dual crisis of energy and fresh water shortage. However, the high abundance of seawater resources is faced with the dilemma of complex composition and difficult purification .…”

Rapid “self-healing” behavior induced by chloride anions to renew the Fe–Ni(oxy)hydroxide surface for long-term alkaline seawater electrolysis

“…Directly using natural seawater to produce hydrogen by electrolysis is an effective way to promote the development of sustainable energy and save freshwater resources in the future. [1][2][3][4] If natural seawater without being strictly purified is used as the raw material, the key technical bottlenecks of the electrolysis process are as follows: (1) the chlorine evolution reaction (CER) of the anode will become a competitor of the oxygen evolution reaction (OER), thus reducing the efficiency of water splitting; (2) a large number of aggressive chloride anions in seawater will seriously corrode anode metal-based electrocatalysts; (3) some biological factors and interference ions will cause the occupation of active sites of electrocatalysts leading to inactivation. [5][6][7][8] Although it can easily avoid the problem of chloride evolution with a low OER equilibrium potential, 9,10 the fluffy lamellar structure will be more conducive to the surface adsorption and interlamellar insertion of chloride ions, 11,12 especially for some layered double hydroxides.…”